1. Field of the Invention
This invention relates to radiographic systems and more particularly to an interactive digital radiographic system which controls both the radiation source, and the radiation detector, and guides an operator through the necessary steps to complete a requested examination
2. Description of Related Art
Radiographic examinations entail obtaining at least one and often multiple radiograms of a patient. To obtain such radiograms it is necessary to have a radiation source such as an X-ray machine, and a radiation detector such as radiation sensitive film or other radiation detector. The radiation is imagewise modulated as it passes through an object having varying radiation absorption areas.
In the past decade there has been great progress made in the area of direct radiographic imaging using electronic detectors comprising a two dimensional array of minute sensors to capture a radiation generated image. Information representing an image is captured, often as a charge distribution stored in a plurality of charge storage capacitors in individual sensors arrayed in a two dimensional matrix. We will refer to such detectors generically as electronic detectors to differentiate them from the traditional radiography detectors which employ a photosensitive film usually in combination with an intensifying screen to produce a photographic image of the incident X-ray radiation.
The electronic detectors typically comprise a two dimensional array of sensors with associated switching and addressing circuitry built on an insulating substrate, usually a glass plate. U.S. Pat. No. 5,319,206 issued to Lee et al. on Jun. 7, 1997, shows a typical direct radiation detector comprising an array of sensors for the generation and capture of charges following exposure to X-ray radiation. Readout of the stored charges is accomplished in any one of a plurality of manners. U.S. Pat. No. 5,648,660 issued to Lee et al. discloses a method for the readout of stored charges in a electronic imaging panel.
The availability of a radiogram in electronic signal format, permits the use of digital signal conversion and all the advantages of signal storing, retrieval and processing associated with digital imaging.
At many medical institutes a radiographic examination procedure begins with a Doctor requesting from the department of Radiology to obtain one, or a series of radiograms, of a patient. The request form typically includes the following information:
(a) Patient demographic data, such as social security, patient I.D. name, data of birth, address, insurance etc.
(b) Examination requester information, such as name of Doctor requesting examination and his department.
(c) Examination procedure such as modality (X-ray, Cat Scan, etc.) region (Chest, extremities, etc.) and procedure (frontal, lateral, number of views, placement of patient, etc.).
In a typical Hospital today, the doctors no longer request specific views and exposures for each patient, but simply identify specific examinations by a name or code. The actual exposure procedures corresponding to these examinations are predetermined and the radiology technician simply follows these predetermined procedures once he receives the examination request code.
With the availability of digitized images, picture archiving and communication systems (known as PACS) have been developed which store, communicate and display images and other data on demand at various locations. In a typical PACS application the system stores image data sent from x-ray, CT, MRI and other imaging systems in a database, and transfers requested image data from the database to an image workstation. The image workstation displays received image data on a cathode ray tube (CRT) display for study by the doctor, who, following his study of the image may prepare a report and attach the report to the image for future reference when the image or report are needed again. The image workstation may also display the image as a hard copy printed locally by a local printer connected to the PAGS system.
Yet, in spite of the availability of direct radiation capturing devices and PACS systems, there has not been developed as yet a system which integrates a number of distinct functions of individual modalities, output devices, and existing systems into an integrated interactive radiographic imaging system able to provide faster access to better diagnostic images and to greatly reduce the possibility of operator error.
It is an object of this invention to provide such an integrated system which offers the advantages of complete radiation exposure control, image capture, storage and display combined with interactive operator guidance through the examination specific steps in combination with the use of predetermined default settings automatically recalled, to complete a requested procedure.
It is thus the object of the present invention to provide an interactive integrated medical radiographic system comprising in combination:
a radiation source;
an electronic detector including an analog to digital converter;
a central control device including a CPU and a user interface; and
a memory.
More particularly, the radiation source emits on command a radiation beam that is directed to pass through a target and impinge on the electronic radiation detector. Still according to this invention, the central control device is in communication with both the memory, the radiation source, and the electronic detector.
The central control device is programmed to interact with an operator through the user interface and in response to input by the operator through the user interface, and data stored in the memory, to initialize said imaging detector, to set said radiation source for a desired exam, to retrieve from memory a sequence of steps representing actions by the operator required to perform said desired exam, and to sequentially guide the operator through said sequence of actions.
The radiographic system typically will also include a display device on which the central control may display, after appropriate formatting, an image captured by the electronic detector following exposure of a target to imaging radiation. The central control may be further programmed to retrieve from the memory an Exam Specific Algorithm (ESA) and to apply this algorithm to the exposure data representing the radiogram prior to displaying it.
The ESA may be applied as a default image correction or may be selected by the operator from a plurality of ESAs stored in memory through the user interface.
In displaying a radiogram on a selected output display device, the central control may further include an interactive link between said control and the display device whereby the control identifies the display and formats the data for display in a format acceptable by the display device.
The central control may be further programmed to accept alpha-numeric input data representing demographic patient and exam data, to store the data, and to associate the data with a particular radiogram.
It is also an object of this invention to provide a program embodied in a machine readable medium for programming a control computer to control a radiation source to emit a radiation beam directed to pass through a target and to impinge on an electronic detector. The machine readable program instructs the computer to perform the following steps in response to information and commands entered by an operator through a computer user interface, and from data stored in a memory and retrieved therefrom:
i) to initialize the imaging detector and the radiation source;
ii) through the user interface, to guide the operator through a sequence of actions needed to expose to the radiation beam a target, typically a patient; and
iii) to retrieve and store the exposure data in the memory.
The machine readable program further includes instructions for the computer to prompt the operator to evaluate and to accept and reject exposure data from the detector prior to storing the exposure data. The exposure data represents a radiogram of the target.
In addition, the machine readable program further includes instructions for the computer to apply selected image processing algorithms to the exposure data and to format and transmit the exposure data for display on a display device after it has interrogated the display device about display format requirements and having formatted the exposure data in a format acceptable to the display device.